Experimental Study On Vibration Reduction Performance Of Electrorheological Fluid Sandwich Beams

The operation of various types of power machines,the operation of transportation tools,the driving of construction sites,drilling,and artificial blasting,etc.,all generate vibrations.Some vibrations with large energy may cause harm to human bodies or objects.The engineering measures to control vibration include reducing disturbance,vibration isolation,and preventing resonance.The specific measures include changing the natural frequency of the vibration system,changing the frequency of disturbances to the vibration system,increasing the damping of the system and reducing the vibration amplitude.Electrorheological fluids are smart materials whose rheological properties can be controlled by an external electric field.By adjusting the strength of the applied electric field,the apparent viscosity,yield strength and other properties of the ER fluid can change rapidly and continuously and reversibly.Because electrorheological fluids have the advantages of fast response,low energy consumption,wide range of mechanical properties,simple placement and control methods,etc.,they have attracted wide attention from scholars at home and abroad in vibration control of flexible structures.This paper studies the vibration damping characteristics of electrorheological fluid sandwich beams and provides ideas for exploring the use of ER fluids in the intelligent control of vibration.In this paper,the controllable mechanical properties of electrorheological fluid are used to apply the ER fluid to the sandwich structure to form a sandwich beam.The damping and stiffness of the system are adjusted by the external electric field to achieve the purpose of vibration reduction.In this paper,the composition,performance and mechanism of electrorheological fluids are reviewed.The electrorheological fluid is treated as a viscoelastic material and its mechanical model is established.The finite element method is used to divide the sandwich beam into a finite number of units,and the sandwich beam element is analyzed.For the differential equation of motion,the energy formula of the unit is obtained.The Hamilton variational formula is used to obtain the dynamic equation of the sandwich beam element.Then the dynamic equation of the entire ER fluid sandwich beam is obtained through unit integration,and the Matlab calculation program is written according to the dynamic equation.Substituting the physical parameters of the ER fluid sandwich beams,the natural frequencies and loss factors of the ER fluid sandwich beams under different electric field strengths are calculated,and the vibration characteristics of the ER fluid sandwich beams are analyzed.In this paper,ER fluids were prepared using starch,CTO particles and dimethyl silicone oil.Electrorheological fluid sandwich beams were prepared using aluminum alloy thin plates.By the method of cantilever beams,exciter was used to stimulate ER fluid sandwich beams,the eddy current sensor was used to measure the vibration displacement signal,a vibration experiment system was designed and an experimental platform was set up to study the characteristics of electrorheological fluid sandwich beams in vibration reduction applications.In this paper,the influencing factors of vibration damping performance of electrorheological fluid sandwich beams are studied from the aspects of self-characteristics of ER fluids and external conditions of ER fluid sandwich beams.In terms of the characteristics of electrorheological fluids,the influence of the type of ER fluid dispersed particles,the mass fraction of particles,and the viscosity of silicone oil on the damping properties of electrorheological fluid sandwich beams was obtained;the external conditions of ER fluid sandwich beams were obtained.The influence of electric field intensity,excitation frequency and excitation amplitude on the damping properties of ER fluid sandwich beams.